Merocyanine dyes containing a chain substituent



United. Patent Qfice 2,743,273 Patented Apr... 24, 195.6;

MEROCYANINE DYES CONTAINING A CHAIN Edward Bowes Knot't, Wealil'st'one, England, assignor to Eastman Kodak Company, Rochester, N. Ya, a corpration of New Jersey No Drawing, Application. September 15, 1952, Serial No. 309,743

Claims. (Cl. 260-24014) This invention relates to. merocyanine dyes containing a chainisubstituent... Morepa-rticularly, this: inventionire latesto merocyanine. dyes. egntaining: an alkox-yl substituent on the-chain. 5-"

Certain merocarbocyanirie dyes containing an alkoxyl substituent' om the cliain have be'em previously described See, for example, Brooker and White US. Patents 2,478,366, issued August 9, 1949, and 2,494,031, issued January 10,1950. The merocarbocyanine dyes ofiBrooker and White have alkoxyl groups attached to the: carbon atom adjacent to the=basienueleus-,. andthe ketomethylene nuclei are rhodanine or 2-thio-2,4(3,5)-oxazoledione.

I have found a new class of merocyaninedyes containing;an.alkoxy1. group. attachedfltothe. carbon atom adjacent to. the. ketomethylene: nucleus, and wherein. the ketomethylenenucleusiisof a certain type.

It. is, accordingly, an objectof my invention to provide new merocyanine: dyes. Stilhanothen object: isto provide a method for making-these new dyes. Another object. is

to providenphotographicsilver-halide emulsions sensitized. with my new dyes. Other objects will become apparent from the following description and: examples,

The new merocyanine dyes: of my invention. can be represented by the following general formula:

metallic atoms necessary to complete a heterocyclic' nucleus containing fromfive to-six' atoms in the heterocyclic ring, such as thoseselected from the group consistingof those of the thiazole series (e g. thi'a zole, 4-methylthirobenzoxazol'e, 5Q methylbenzoxazole, 5 --phenylbenzoxa=+ azole, 4-phenyl'thiazole, S methyIthiaZoI'e; S lienyI-thiazole, 4,5-dimethylthiazole, 4,5-diphenylthiazole, 4-(2-thienyl-Dthiazol'e, etc), those of the benzothiazole series (e. g; benzothiazole, 4-elilorobenzothiazolm 5-chlorobenz0- thiazole, 6-ch1orobenzotliiazol'e; 7-clilorobenzotliiazole, 4- methylbenzothiazole, 5 methylbenzothiazole, 6' --methylbenzothiazole, 5bromobenzothiazole, 6-bromobenzotliia zole, 4 -phenylbenzothiazd le, 5*-phenylbenzothiazole, 4- methoxybenzothiazol'e, 'S-rhethoxybenzothi'znzolb, S-methoxybenzothiazole, 5-iodobenzothiazole, 6-iodobenzothiazole, 4-ethoxybenzothiazole, S-ethoxybenzothiazol'e, tetrahydrobenzothiazole, 5,6-dimethoxybenzothiazole; 5-,6 -di oxymethylenebenzothiazole, S-hyd'roxybenzothiiazolb, 6- hydroxybenzothiazole, etc.), those of the naphthothiaz ole series (e. g. a-naphthothiazole, fi-naphthothiazole, 5-meth'- methoxy-a-naphthothiazole, 7-methoxy-a-naphthothiazole,

201e, 6 methylbenzoxazole, 5 ,6dimethylhenzoxazole,4g6- dimethylhenzoxazole, 5 methonybenzoxazole, .5? -ethoxybenzoxazol'e, 5 chlorobenzoxazole-,,6.- methoxybenzoxa 291e,,ihydroxybenzoxazole; 6-hydroxybenzoxazole, e-te,),. those- 0f, the, naphthoxazoleseries (e. g. ac-naphtlioxazole, fi-naphthoxazole, etc. thoseofi the selenazole series .(e; g;.; 4.-methylselena zole, 4-phenylselenazo'le, etc..)p, thoseof the: benzoselenazole. series (e. g.. benzoselenazole, 5.-chlor.o,- benzoselenazole,, 5- methoxybenzoselenazole, 5- hyd-roxyhenzoselenazole, tetrahydrobenzoselenazole, etc..)-,, those ofIthe naphthoselenazole. series (e. g, a-naphthoselenazole, flrnaphthoselenazole, etc.),, those of the thiazolinei series-- (2:. g. thiazoline, 4'-methylthiazolfine, etc), those of the Z-quinoline series (e. g, quinoline, 3-methylquinoline, 5"- methylquinoline, 7-methylquiiJ-ol'ine, 8 -methylquinoline, 6- chloroquinoline, 8-chl0roqninolineg, 6-methoxyquinolinc;. firethoxyquinoline, 6 -hydroxy quino1ine,. 8ehydr,oxyqnino line,-. etc), those- 05 the: 4-quinoline series, (i'e; g. quinoline, 6Fmeth0xyquinoli-nc,. 7 met-hylquinoline, 8- methylquinoline; etc. those. oil the l-isoquinoline series (;e:-. g.. i507 quinoline; 3,4-dihydroisoquinoline,, etc), those1of. the: 3-

isoquinoline. series (e. g; isoquinoline', etc. ),.t-hose:ofither.

thelpyridine series- (e. g. pyridine, S-methyIpyridine, etc),

etc., and.Q representsthe non-metallicatoms necessary to.

complete, a nucleus selected from the; group consisting of" those. of: the 5t(4);-thiazolone series,,. those of. the: 5C4)?- oxazolone:v series, those; of th'e%5,(.4) -isoxazol'one. series, and:

those 013' the 1 ,3-indandione series. In.- accordance with my invention, I; provide the dyes of Formula In above wherein d" is 1:. byv reactingi together 2. compound selectedfrom. thoserepresented by the following general formula II. z

R-1| f cH-0H T= Y3 s-R2 wherein R, n, and Z have the values given above, X represents an anion, such as chloride, bromide, iodide, perchlorate,, sulfamate, thiocyanate; nitrate; p-toluenesulfonate, benzenesulfonate, methylsulfate, ethylsulfate, etc.,, and Rarepresentsan alkyl group, such as methyl, ethyl, ben-zyl (phenylmethyl), etc. or. an aryl. group, such as phenyl, p-chlorophen'yl, p-tolyl, etc.,, with a compound selectedfrom. thoserepresented by the following general. formula III. 0R

one-(i=6 b=o wherein, R1 and Q each have the values given. above.

in accordance? with my invention, I provide the. dyes wherein R, n, X, and Z each have-the values giveniabove, R3 represents an: acyl' group, such as acetyl, propionyl, benzoyl, etc., and R4 represents an aryl group, such as phenyl, 0-, m-, and p tolyl, etc., with a compound selected 'from those represented by Formula III above.

The condensation of the compounds of Formula II a maavs with those of Formula III, or those of Formula IV with thoserof Formula III, can becarried out in the presence of a basic condensing agent, such as the trialkylamines (e. g. triethylamine, tri-n-propylamine, tri-n-butylamine, triisobutylamine, etc.), N-alkylpiperidines (e. g. N-methylpiperidine, N-ethylpiperidine, etc.), N,N-dialkylanilines (e. g. N,N-dimethylaniline, N,N-diethylaniline, etc.), etc. The condensations can advantageously be carried out in the presence of an inert solvent, such as pyridine, lower aliphatic alcohols (e. g. ethanol, n-propanol, n-butanol, etc.), 1,4-dioxane, etc. Heat accelerates the condensations, and temperatures varying from room temperature to reflux temperature can be used.

' The intermediates of Formula III above wherein Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus of the 5(4)-oxazolone series can be prepared according to the process described in Ilford British Patent 633,736, accepted December 19, 1949; The intermediates of Formula III wherein Q represents the non-metallic atoms necessary to complete an indandione or a 5 (4)-isoxazolone nucleus can advantageously be prepared by condensing together a 1,3-indandione or 5(4)-isoxazolone with an alkyl orthoacetate selected from those represented by the following general formula:

wherein R1 has the values given above, in the presence of a carboxylic anhydride, such as acetic anhydride, propionic anhydride, etc. The intermediates of Formula III above wherein Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus of the 5(4)- thiazolone series can advantageously be prepared according to the methods described by Cook et al., Jour. Chem. Soc. (1949), pps. 1435-7, and in The Chemistry of Penicillin, Princeton Univ. Press (1949), pg. 803. (For a further description, see the copending application Serial No. 211,566, filed February 17, 1951, in the names of Per Aubert and Edward B. Knott, now U. S. Patent 2,692,829, issued October 26, 1954 and my copending application Serial No. 224,714, filed May 5, 1951, now U. S. Patent 2,691,581, issued October 12, 1954.)

The following examples will serve to illustrate more fully the manner whereby I practice my invention.

Example 1.4-[a-ethoxy-2-(1-ethyl-2(1 -quinlylidene) ethylenej-Z-ethylthio-S (4) -thiazol0ne 0.9 g. of N-dithiocarbethoxyglycine, 7 cc. of acetic anhydride, and 2.5 cc. of ethyl orthoacetate were heated at 120 C. for one hour allowing the alcohol to escape. The solvents were removed under reduced pressure, and 2.5

g. of 2-ethylthioquinoline etho-p-toluenesulfonate, 10 cc.

Example 2 .4- [m-ethoxy-2-(3-ethyl-2 (3 -benzothi0az0 lylidene ethylidene] -2-phenyl-5 (4 -0xazol0ne The dye (1.05 g., 54.5%) formed green 2.5 g. of 2-ethylthiobenzothiazole etho-p-toluenesulfonate, 1.15 g. of 4-(a-ethoxyethylidene)-2phenyl-5(4)- oxazolone, 5 cc. of n-propanol, and 0.8 cc. of triethy1- amine were refluxed together for 10 minutes. The orange solution deposited the dye after chilling, and seeding with a stirring rod by scratching. The dye weighed 0.8 g. (50%) and formed orange threads, M. P. 198 C., from ethanol.

Example 3.4- [u-eIhOxy-Z- (I -ethyl-2 (1 )-quin0lylidene) ethylidene] -2-phenyl-5 (4 -0xaz0l0ne 0 coin, ii-o -CuBs N N CH- 0.8 g. of Z-ethyIthioquinoline etho-p-toluenesulfonate,

0.5 g. of 4-(a-ethoxyethylidene)-2-phenyl-5(4)-oxazolene,

5 cc. ethanol, and 0.4 cc. of triethylamine were refluxed together for 30 minutes. The mixture was chilled overnight, and 0.2 g. (10%) of crystals was collected. They formed violet laths, M. P. 146 C., from ethanol.

Example 4 .4 [a-ethoxy-4-(1-ethyl-2 (I )-quinolylidene) but-2'enylidene] -2 phenyl-5 (4 -oxaz0l0ne O OCZHQ 0 Example 5 .-4-[a.-eth0xy-4- (1 -ethyl-2 (1 -quin0lylidene) but-Z-enylz'dene] -2-benzylthio-5 (4 -thiaz0l0ne 1.5 g. of 4-(a-ethoxyethylidene)-2-benzylthio-5(4)- thiazolone, 2.2 g. of 2B-acetanilidovinylquinoline eth-- iodide, 10 cc. of ethanol, and- 0.8 cc. of triethylamine were refluxed together for 30 minutes. After chilling and standing overnight the dye separated. It was dissolved in 20 cc. of benzene and insoluble matter (carbocyanine dye) filtered 011. The filtrate was concentrated to 4 cc. and 15 cc. of ethanol added. The dye (1.1 g., 46.5%) formed glittering, dark green needles, M. P. 168 C., on chilling. It sensitized a gelatino silver chlorobromide emulsion with maxima lying at 675 and 730 mu.

The 4- a-ethoxyethylidene 2-benzylthio-5 (4 -thiazolone used above was prepared as follows:

24.1 g. of N-dithiocarhobenzyloxyglycine, 30 cc. of ethyl orthoacetate, and cc. of acetic anhydride were heated at 125 C. for one hour on an oil bath, the ethanol formed in the reaction being allowed to distill. Removal of the solvents from the solution at C./l0 mm. left a brown oil which was used directly in the dye condensations. 7

Examples 6 to 17 below describe various merodicarbocyanine (tetramethinemerccyanine) dyes. These dyes.

were prepared in the same manner as those of Examples 4 andS above, using either the 4-(ot-ethoxyethylidene)- oxyethylidene) -2-benzylthio-5 (i4) -thiazolone of Example 5;. together with the appropriate: 2'-p-aeetanilidoviny1 quaternary salt. The method: of recrystallization? was the same: I'm those cases where the: dye tended to separate as an oil-,.the dye was obtained as czystals by seeding (i e. "lnoc"ulation)l.

Example 6.4 [a ethoxy 4 (3 ethyl 2(3)- benzxazolylidene)but 2 enylia'ene] 2 phenyl- (4 -oxa-z0lbn'e This dye: was obtained as magenta threads; in 85% yield. It had a melting point of 191 C.

Example 7.4- [a ethoxy 4 (3 ethyl 2(3)- benzoxazolylidendbut 2. enylidenel 2'1 benzylthio-5-(4)-thiazolone This dye was obtained. as blue needles int 35% yield. It hada melting point of 122'? CL and. sensitized a phot graphic gelatino silver chlorobromide emulsionl with. maxima at 570 and" 63011111,. and. a photographie. gelar tino silver bromiodide emulsion with a maximum at 620111; 7 1 t Example 8.4 [a ethoxy 4 (3 ethyl 2(3)- benzothiazolylidene) but 2 enyliderte] 2 phenylo=o11on=o11 m (Last.

This dyewas' obtaihe'd' as mauvethreads in 87% yield. It had a melting point of 178 C; and sensitized a photographic gelatino silver ehlorobromide emulsion with a maximum at 600 mu and a photographic gelatino silver bromiodide emulsion with a maximum: at 595 mu.

Example 9.4 [a ethoxy 4 (3 ethyl 2(3)- benzothiazolylidenflbut 2 enylidene] 2 benzyl- This dye was o btained' as brilliant green crystals in 50% yield. It had a melting pointof142 C. and it sensitized a photographic gelatino silver chlorobromide V emulsion with maxima at 560 and 590 mu and a photographic gelatino silver bromiodide emulsion with maxima at 610 and 650 mu.

This dye was obtained as grey-green threads in 90% .yield. It had a melting point of 156 C. and it'sensitized a photographicgelatino. silver chlorobromides emulsion with a maximum att 6-2Qtmu and a: photographibgelatinol silver bromiodide emulsionwithmaxima at 570. mu and Example 11.-4 [a Q ethoxy 4 (3 ethyl 2(3)- benzoselenazolyli dene) but 2 enylidene] 2 benzylthin-5 (,4)-tliiaz0l'one Hs K as yield; Ithada meltihg-point of 20'7 (3.

Example; 13.4 a ethoxy 41- (3- methyl 2('3-)- Z Hs.

This dye was obtained as glossy, steel-blue spears in 33.5% yield- It had a melting point oh 126 C. and it sensitized a photographic gelatino silver chlorobromide emulsion with. maxima at 530 and 640 mu and a photographic .gelatino silver bromiodide emulsion with maxima at 5-70 and610-mul This: dye was obtained as: dark maroon fl'akes 68-%- This dye was obtained as' jagged, steel-blue needles in 42% yield.. It had a melting point of 155 C.

Example 16.4-[a-eth0xy-4-(1-eihyl -w 4 (1 quinolyli dene) but-2-enylidene]-2-phenyl-5 (4 -oxazolne This dye was obtained as glittering green crystals in 57% yield. It melted at 202 C.

Example 17.4 [u-ethoxy-4-(4,5-diphenyl-3-ethyl-2 (3 thiaz0lylidene)but 2 enylidene]-2 phenyl-S (4)-oxazolone This dye was obtained as glittering green crystals in 35% yield. It melted at 210 C. and it sensitized a photographic gelatino silver chlorobromide emulsion with maxima at 610 and 650 mu and a photographic gelatino silver bromiodide emulsion with maxima at 620 and 660 mu.

Examples 18 and 21 below describe various merodicarbo-cyanine (tetramethinemerocyanine) dyes. These dyes were prepared in the same manner as those of Examples 4 and 5 above, using 2-(a-ethoxyethylidene)-1,3- indandione and 4 (a ethoxyethylidene)-3-phenyl-5(4)- isoxazolone, respectively, together with the appropriate Z-B-acetanilidovinyl quaternary salt. The'method of recrystallization was the same, seeding being used where necessary. The dyes of Examples 19, 20, 22, and 23 were prepared in the same manner as the dyes of Examples 1 and 2, except that benzene was used as the recrystallizing solvent, either Z-(a-ethoxyethylidene)1,3-indandione or 4-( aethoxyethylidene)-3-phenyl-5 (4)-isoxazolone being used together with 2 ethylthiobenzothiazole etho-ptoluenesulfonate or Z-ethylthioquinoline etho-p-toluenesulfonate.

Example 18. 2- ethoxy-4-( 3-ethyl-2(3)-benzoxaz0lylidene) but-Z-enylidene] ,3-indandione Y O O\ O C H a I 5 p a o=oHoH==oH-b==o 9 1115 (i This dye was obtained as violet needles in 57% yield. It had a melting point of 202 C.

The Z-(a-ethoxyethylidene)-1,3-indandione used in preparing the dye of the above example was prepared as follows:

.8 14.6 g. of 1,3-indandione, 25 cc. of ethyl orthoacetate and 25 cc. of acetic anhydride were heated together on an oil bath at 140 C. for one hour.- The solvents werev removed under reduced pressure and the solid residue recrystallized from ethanol. It weighed 12.7 g. (59% yield) and formed brown needles, M. P. 95111 C.

' Example 19.-2 [a-eth0xy 2-(3-ethyl 2 (3)-benz0thiaz0- lylidene) ethylidene1-1,3-indandi0ne s t I E ouon-zl d V N/ o (IHH,

This dye was obtained as red needles in 74% yield. It had a melting point of -196 C.

Example 20.-4 a-ethoxy-2-(3-ethyl-2 (3 -benz0thiaz0lylidene) ethylidene] -3-phenyl-5 (4 -isoxaz0l0ne Example 21 .4-[a-ethoxy-4-(3-ethyl-2 (3) -benz0xaz0lylidene) but-Z-enylidene]-3-phenyl-5 (4 -is0xaz0l0ne This dye was obtained as red crystals in 55% yield. It had a melting point of 215 C.

Example 22 .4-[a-ethoxy-Z-(1 -ethyl-2 (1 )-quinolylidene) ethyl idene1-3 -ph eny l-5 (4) -is0xaz0lone This dye was obtained as garnet aggregates in 41% yield. It had a melting point of 195 C., and it sensitized a photographic gelantino silver chlorobromide emulsion with a maximum at 590 mu.

Example 23.2-[a-eth0xy-2-(1 -et hyl-2 (1 )-quinolylidene) ethylidene1-1 ,S-indandione O 0 C 3H N CHI-( This dye was. obtained greentneedles. 22% yield. It had a melting point of 2V6 C. p

As shown in a number of the-above Xdrnplesgthe-neW dyes of my invention are useful-11f s'pectrau sensitizing photographic silver halide emulsiolisj when incorporated therein. The dyes areespecially-usefii'l for extending; the spectral sensitivity of the customaril y e'niployed gelatiito silver chloride, gelatino: silver oltlorobr'omide, gelatino silver bromide, gelatino silver bromiodide, and gelatino silver chlorobror'r'iiodide developing-out emulsions". In several of the foregoing examples, the point of maximum sensitivity of gelatino silver chlorobromide and/or gelatino silver bromiodide emulsions sensitized with my new dyes is pointed out in connection with the description of the properties of certain of the dyes. To prepare emulsions sensitized with one or more of my new dyes, it is only necessary to disperse the dye or dyes in the emulsions. The methods of incorporating dyes in emulsions are simple and are known to those skilled in the art. In practice, it is convenient to add the dyes to the emulsions in the form of a solution in an appropriate solvent. Methanol or acetone has proved satisfactory as a solvent for most of my new dyes. Where the dyes are quite insoluble in methyl alcohol, a mixture of acetone and pyridine is advantageously employed as a solvent. The dyes are advantageously incorporated in the finished, washed emulsions and should be uniformly distributed throughout the emulsions.

The concentration of the dyes in the emulsions can vary widely, e. g. from 5 to 100 mg. per liter of flowable emulsion. The concentration of the dyes will vary according to the type of emulsion and according to the effect desired. The suitable and most economical concentration for any given emulsion will be apparent to those skilled in the art, upon making the ordinary tests and observations customarily used in the art of emulsion making. To prepare a gelatino-silver-halide emulsion sensitized with one or more of my new dyes, the following procedure is satisfactory:

A quantity of dye is dissolved in methyl alcohol or acetone (or a mixture of acetone and pyridine) and a volume of this solution, which may be diluted with water, containing from 5 to 100 mg. of dye, is slowly added to about 1000 cc. of gelatino-silver-halide emulsion, with stirring. Stirring is continued until the dye is thoroughly dispersed in the emulsion.

With most of my dyes, from to 20 mg. of dye per liter of gelatino-silver-bromide or bromiodide emulsion (containing about 40 g. of silver halide) suflices to produce the maximum sensitizing elfect. With the finer grain emulsions, somewhat larger concentration of dye may be needed to produce the maximum sensitizing effect.

The above statements are only illustrative, as it will be apparent that the dyes can be incorporated in photographic emulsions by any of the other methods customarily employed in the art, e. g. by bathing a plate or film upon which an emulsion is coated in a solution of the dye in an appropriate solvent. However, bathing methods are ordinarily not to be preferred. Emulsions sensitized with the dyes can be coated on suitable supports, such as glass, cellulose derivative film, resin filmor paper in the usual manner.

What I claim as my invention and desire secured by Letters Patent of the United States is:

1. The merocarbocyanine dye having the following for- 2. The merocarbocyanine dye having the following formula:

3. "line r'rierodicarboeyanine. are having die: renewin formula? 4. The merodicarbocyanine dye having the following formula:

5. The merodicarbocyanine dye having the following formula:

6. A process for preparing a merocyanine dye cornprising condensing a cyclammonium quaternary salt selected from the group consisting of those represented by the following two general formulas:

and

wherein R represents an alkyl group of from 1 to 4 carbon atoms, R2 represents a member selected from the group consisting of an alkyl group containing from 1 to 7 carbon atoms and a monocyclic aryl group, R3 represents a carboxylic acyl group, R4 represents a monocyclic aryl group, X represents an anion, n represents a positive integer of from 1 to 2, and Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of those of the thiazole series, those of the benzothiazole series, those of the naphthothiazole series, those of the thianaphtheno- 7',6,4,5-thiazole series, those of the oxazole series, those of the benzoxazole series, those of the naphthoxazole series, those of the selenazole series, those of the benzoselenazole series, those of the naphthoselenazole series,

-those of the thiazoline series, those of the 2-quinoline series, those of the 4-quin0line series, those of the 1- isoquinoline series, those of the 3isoquinoline series, those of the 3,3-dialkylindolenine series, and those of the pyridine series, together with a compound selected from those represented by the following general formula:

0R]. //Q\\ ouhd= c=o wherein R1 represents an alkyl group and Q represents the nonmetallic atoms necessary to complete a nucleus selected from the group consisting of those of the 5(4)- 1 1 thiazolone series, those of the 5(4)-oxazolone series, those of the 5 (4)-isoxazolone series, and those of the 1,3- indandione series.

7. A process according to claim 6 wherein the said process is carried out in the presence of a basic condensing agent.

8. A process according to claim 6 wherein the said cyclarnmonium quaternary salt is a quinolinium salt.

7 9. A process according to claim 6 wherein the said cyclammonium quaternary salt is a benzoxazolium salt.

10. A process according to claim 6 wherein the said cyclammonium quaternary salt is a benzothiazolium salt.

References Cited in the file of this patent UNITED STATES PATENTS Keyes June 2, 1940 Brooker Aug. 9, 1941 Brooker Jan. 10, 1950 Kendall June 12, 1951 Aubert Oct. 26, 1954 FOREIGN PATENTS Great Britain 1937 

1. THE MEROCARBOCYANINE DYE HAVING THE FOLLOWING FORMULA: 